A. Field of the Invention
The present invention relates to improvements in electric fasteners driving tools.
B. Description of the Prior Art
Electric tools for driving fasteners such as brads, staples and the like are well known and widely used. Examples of tools of this character developed in the past may be found in U.S. Pat. Nos. 3,141,171; 3,172,121; 3,179,866; 3,434,026; and 4,005,812. All assigned to the assignee of the present application. Such tools commonly include a housing with a handle portion and a head portion. The head portion contains a solenoid winding for accelerating an armature. Typically, a control circuit for energizing the winding is operated by a switch in the handle portion. A magazine is carried by the base of the head portion and by the handle for introducing fasteners into a drive track to be driven by a driver blade supported by the armature.
The present invention relates to improvements in electric fastener driving tools of this type. Among the important objects of the present invention are to provide a tool that is light in weight, is easily and economically manufactured and includes a member that may be used to allow the tool to drive fasteners into the grooves of a grooved workpiece or a flat workpiece and to vary the depth into which the fasteners are driven.
Another object of the present invention is to provide a new and improved electric fastener driving fastener tool including a novel safety that prevents energization of the tool until the tool engages the workpiece.
A further object of the present invention is to provide an electric fastener tool with a pusher assembly including a bifurcated tube defining a gap within which the pusher is mounted with a spring biasing the pusher towards the drive track of the tool. The fasteners are positioned within the gap and between the two portions of the tube.
An additional object of the present invention is to provide a new and improved magazine assembly that is pivotally mounted to the housing of the tool and includes a fastener's track that may support and guide fasteners of different sizes.
Another object of the present invention is to provide a new and improved shoe removably secured to the bottom of the magazine structure of the tool to enable the tool to be used for workpieces that are either grooved or flat and also to allow variation of depth to which the fastener is driven into the workpiece.
The present invention is directed to a new improved electric fastener nailer for driving fasteners into a workpiece and, in particular, into grooved workpieces and also for driving fasteners into different levels in the workpiece. The electric fastener driver of the present invention includes a body defining a head portion and a handle portion. The body is of a clam shell configuration formed of two similar plastic body parts including integral walls forming a solenoid chamber in the head portion and forming a mounting position for a switch and related circuitry in the handle portion. A magazine for supplying fasteners to be driven is pivotally supported on the handle portion. A driver is secured to the solenoid for reciprocation in a drive track defined by the nose portion. Energization of the solenoid and thus of the tool is controlled by a switch that is manually actuated through the employment of a plunger reciprocally mounted in the handle portion.
The tool includes a safety that prevents depression of the plunger until the tool has been placed against the workpiece. The safety is actuated to release the plunger by the pivoting movement of the magazine assembly upon engagement of the tool with the workpiece. More specifically, upon engagement of the tool with the workpiece, the magazine assembly is pivoted from a first position to a second position. The safety is coupled to the magazine assembly and thus moves from a first to a second position in conjunction with the pivoting movement of the magazine assembly. In the second position, the safety is out of engagement with the plunger allowing actuation. The magazine assembly also includes a track that supports and guides fasteners of different sizes.
A pusher assembly for advancing fasteners to the drive track of the tool is included in the magazine assembly. The pusher assembly is defined by a bifurcated, elongated tube defining a gap within which the fasteners are positioned. A pusher is slideably mounted within the gap and biased toward the drive track of the tool by a spring.